In a small bowl, mix powdered sugar and 1/4 cup peanut butter until crumbly. Set aside.
In a large bowl, whisk together pudding mix, milk, and 1/2 cup peanut butter for about 2 minutes until thickened.
Gently fold in 1 cup of whipped cream until smooth.
Sprinkle half of the peanut butter crumbles into the cooled pie crust.
Spread the filling evenly over the crust.
Cover with 2 cups whipped cream or Cool Whip.
Sprinkle the remaining crumbles on top.
Refrigerate for at least 2 hours before slicing. Serve chilled.